This application relates to an oil level sensor that is made to be robust such that it will operate reliably.
Oil level sensors are utilized to ensure a minimum quantity of oil for critical applications. As one example, a gear box for a starter generator on an aircraft must have a proper supply of oil.
Oil level sensors have often been utilized in these applications. One proposed oil level sensor has a tab extending away from a probe. The tab receives a fastener to connect the sensor to a wall of the gear box. The probe extends away from the tab, and into the oil. A resistance thermal device (RTD) is mounted within the probe. Current is passed through the RTD, and the RTD quickly heats. Oil outwardly of the probe cools the probe. However, in the absence of oil, the increased heat will be detected.
The prior proposed probe utilized a shrink wrap over the splice connection between the RTD and the wires leaving the housing of the sensor. The shrink wrap restricted the potting compound from firmly holding the wires, resulting in unsupported wires that broke in high a vibration and/or thermal cycling environment. In addition, the wires leaving the housing had electrically conductive anchors that were crimped to the wires and located near an opening through which they left the housing wall. At times these anchors caused cold flow of the wire insulation, which coupled with the anchor location being near the exit hole, the wires could short to the housing of the sensor. Also, the probe was undesirably thin compared to a height of the probe allowing normal handling during manufacturing and assembly to flex the probe potentially causing breakage of the RTD or wires within the sensor.